Some example devices, such as smartphones, may have an interface allowing individuals to access features of the smartphone. An example of an interface may include, but is not limited to a resistance touch-based interface, a capacitance touch-based interface, a surface acoustic wave-based interface, an optical touch-based interface, an electromagnetic guidance-based interface, among others. Although generally durable, these interfaces are susceptible to unforeseen damage. Therefore, increasing demand for products protecting the interface has influenced the advances made to protective film manufacturing. In the example above, the interface may have a protective film (e.g., a transparent film) installed across it to reduce damage to the interface. While the protective film reduces damage to the interface in case of impact, the protective film may affect the functionality of one or more sensors positioned below the interface. For example, a protective film may defocus ultrasonic fingerprint sensors that may be located underneath the interface.